IBM Research today revealed that solar and wind forecasts it is producing using machine learning and other cognitive computing technologies are proving to be as much as 30 percent more accurate than ones created using conventional ...

High above the bustling city of Honolulu, in a quiet, exclusive hillside neighborhood where some of the island's wealthiest residents live, there is an extravagant home that's not quite like the others.

A major automaker came to Lawrence Berkeley National Laboratory recently wanting to better understand battery degradation. After many months of intense collaborative research with a Berkeley Lab battery scientist, they gleaned ...

Nearly 800 million people worldwide don't have access to safe drinking water, and some 2.5 billion people live in precariously unsanitary conditions, according to the Centers for Disease Control and Prevention. Together, ...

Researchers from the National Astronomical Observatory of Japan (NAOJ), the University of Tokyo and other institutions have begun a wide-area survey of the distribution of dark matter in the universe using Hyper Suprime-Cam, ...

Energy

In physics, energy (from the Greek ἐνέργεια - energeia, "activity, operation", from ἐνεργός - energos, "active, working") is a scalar physical quantity that describes the amount of work that can be performed by a force, an attribute of objects and systems that is subject to a conservation law. Different forms of energy include kinetic, potential, thermal, gravitational, sound, light, elastic, and electromagnetic energy. The forms of energy are often named after a related force.

Any form of energy can be transformed into another form, but the total energy always remains the same. This principle, the conservation of energy, was first postulated in the early 19th century, and applies to any isolated system. According to Noether's theorem, the conservation of energy is a consequence of the fact that the laws of physics do not change over time.

Although the total energy of a system does not change with time, its value may depend on the frame of reference. For example, a seated passenger in a moving airplane has zero kinetic energy relative to the airplane, but non-zero kinetic energy relative to the Earth.